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CryptoHack

A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Do you have good eyes? (Breizh CTF) CTF Archive 0
RSATogether (ECSC 2024 (Italy)) CTF Archive 0
Authentification 1 (Breizh CTF) CTF Archive 0
One Round Crypto (ECSC 2024 (Italy)) CTF Archive 0
Greatest Common Multiple (CODEGATE CTF) CTF Archive 0
Weekly Top Users
#1 Harachili 9180
#2 ciphermalware 3025
#3 s4hm4d 2455
#4 KSokolov 1775
#5 pot123 1750
Recent Solves
XOR Starter Alessio300403
Inferius Prime Yako
Favourite byte jelfixee
SIDH Key Exchange tonyfrg
Factoring Yako
Recent Solutions
Broken RSA boge 0
Logon Zero richwas 0
Missing Modulus Dagurb 0
Manyprime Mashi 0
Monoprime Mashi 0

Level Up

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